The combination of tight straw supplies in the market in recent months and elevated prices witnessed many producers failing to source their normal volume of straw this winter.

Supply issues have been further complicated by inclement weather forcing earlier housing.

Reports from farmers and advisers point to possible shortages, while some producers have acted early to try and conserve supplies, and ensure sufficient volumes are available for the critical lambing period.

Where there is any doubt regarding supplies, then the earlier this is recognised, the greater the options will be to take action.

Straw budget

The first step is to carry out a straw budget. This can start with calculating demand or available supplies.

Lowland ewes on average require 7kg straw bedding each week to absorb all urine and keep bedding relatively clean, while hill ewes require in the region of 4kg to 5kg.

As a rule of thumb, a typical 4x4 round bale of straw weighing 140kg will be sufficient to provide bedding for 18 to 20 lowland ewes per week, or 30 to 35 hill ewes.

This calculation is based on ewes consuming a silage diet with a typical dry matter content of 25%. If hay or haylage are being fed, then the bedding requirement can generally be reduced by 20% to 30%.

This calculation does not take account of the fact that some straw saved this season is of lower quality, with a higher moisture content, and therefore its absorbency should not be overestimated.

The volume of straw required to bed individual pens where ewes and their lambs have a turnaround time of 24 to 36 hours is estimated at four to five 4x4 round bales for every 100 ewes lambing.

This requirement should be increased by 20% to 30% in high prolificacy flocks where a high percentage of triplet-bearing ewes require additional time in the lambing pens.

Weight of bales

The standard weight used for 4x4 round bales is typically 140kg to 150kg, but these can weigh as low as 120kg in poorly packed, low-moisture bales, to 180kg in bales which are well-packed or have a high-moisture content.

Large 8x4x3 bales weigh about 360kg (350kg to 380kg), while 8x4x4 bales vary more in weight, ranging from just under 500kg to upwards of 600kg.

The typical weight is often 520kg to 540kg. The best way to get an accurate weight is to weigh a selection of bales while identifying the moisture content.

Practices to help reduce demand

There are a number of practices that can be used to try and reduce straw demand and target supplies to when they are needed most. Here are a few:

  • Delay housing: Where a percentage of ewes are being retained outdoors for longer then older ewes, those with a lower body condition score and multiple litters should be housed for preferential treatment, leaving mature and single-bearing ewes better able to withstand the elements outdoors. Ewes should be supplemented outdoors, refraining at all costs from grazing fields closed for grazing post-lambing.
  • Change forage type: As mentioned already, feeding ewes on hay/haylage will reduce straw usage by as much as 20% to 30%.
  • Straw-blower: For users of large volumes of straw, the use of a straw chopper/blower can reduce usage, with some farmers claiming upwards of 10% less straw usage.
  • Ventilation and moisture: It goes without saying that any sources of moisture – such as leaking taps, water troughs, etc – will reduce the effectiveness of bedding, but ventilation can also have a role to play, with poorly ventilated buildings harbouring more moisture and increasing the bedding requirement.
  • Bedding type: There are not too many alternative bedding materials available, but for some, peat, woodchip or sawdust may fit in to the system. Peat is not really suitable for lambing, but can work pre-lambing to conserve supplies.

    • In contrast to cattle, sheep are not heavy enough to turn up a new layer of peat and, as such, the bedding may need intervention from time to time. Woodchip is similar, with machinery required to keep the bed fresh. Both, however, can be used as a base layer under straw, to improve soakage and reduce straw usage.

    Sawdust is in demand for manufacturing/burning and, as such, may not be cost-competitive or easy to source. Some farmers have used wood shavings or miscanthus bedding to pretty good effect in individual lambing pens. While a costly option, it can work with some products on the market, such as pine shavings claiming natural properties in keeping diseases like E coli at bay.

  • Floor type: A change in floor type, such as raised slats, is a longer-term investment in reducing straw supplies, but is one that has grown in popularity in recent years. It has taken the form of sheep slats replacing cattle slats or slats being erected above a concrete floor.
  • Outdoor lambing: This is only really a runner where grass supplies, infrastructure and breed type facilitate it. With regard to grass supplies, there needs to be enough grass available to graze ewes without leaving grass supplies deficient in early lactation.